My pleco are dieing. I found two of them on the bottom of the tank not moving and when I check they were dead they both look very pale. I don't see no sign of injures or anything. They are both around 1 inch and non of my crystal red shrimp are dieing so I don't think its a water issues. I don't know if the other two bigger pleco killed them or its something else. Any1 have any clue what could be killing small pleco?